This invention relates to a band charging apparatus for a packing machine for winding a band on a package such as a box or the like, and more particularly to a band charging apparatus which is adapted to feed a band unwound from a reel to a pool box to temporarily store it therein and then feed it to a band feeding and tightening apparatus to charge it therein. Subsequently, the band is fed to a circumference of the package by means of the band feeding and tightening apparatus, which then draws back the band while gripping a distal end of the band to wind the band on the package and tighten it. Then, an overlapped portion of the band is bonded and a portion of the band wound on the package is cut from the remaining part of the band.
A conventional packing machine is generally constructed so as to feed a band unwound from a reel to a pool box provided in the packing machine by cooperation of a pool feed roller of a band charging apparatus and a pool touch roller thereof. The band thus temporarily stored in the pool box is fed to a band feeding and tightening apparatus.
The band feeding and tightening apparatus includes a plurality of pairs of rollers for feeding the band to a circumference of a package. Feeding of the band to the package is carried out by means of an arch structure provided on a table on which the package is placed. More particularly, the arch structure and table are provided with band passages through which the band is fed to the circumference of the package while being formed into an annular shape.
Subsequently, a band gripping and bonding apparatus grasps a distal end of the band and then a return roller provided in the band feeding and tightening apparatus applies a band drawing-back force to the band, resulting in the band being drawn back. The arch structure and table are formed on an inner peripheral surface thereof with a slit, so that the above-described application of the band drawing-back force to the band fed to the arch structure and table causes the band to rush out of the slit, resulting in the band being wound on the package.
The band is then further tightened by a tension roller provided in the band feeding and tightening apparatus. Then, the band is bonded at an overlapped portion thereof by welding or the like by means of the band gripping and bonding apparatus while being kept tightened. Thereafter, the band is cut at a portion thereof wound on the package from the remaining part of the band.
The conventional band charging apparatus described above is disclosed in Japanese Patent Publication No. 5494/1984. Also, Japanese Utility Model Application Laid-Open Publication No. 92904/1985 discloses an improvement in the band charging apparatus disclosed in Japanese Patent Publication No. 5494/1984.
Now, the band charging apparatus disclosed in Japanese Utility Model Application Laid-Open Publication No. 92904/1985 will be described hereinafter with reference to FIGS. 13 and 14.
The band charging apparatus, as shown in FIG. 13, includes a band guide plate means 8 which is adapted to guide a band 1 when the band 1 unwound from a reel (not shown) is fed to a band feeding and tightening apparatus (not shown). For this purpose, the band 1 is guided through a band inlet port 4a into the band guide plate means 8 by means of a pair of pool rollers 5 and then fed from a band outlet port 4b through a band passage 8' to the band feeding and tightening apparatus by means of a pair of feed rollers 7, resulting in being charged in the band feeding and tightening apparatus. When charging of the band 1 in the band feeding and tightening apparatus is completed, the band guide plate means 8 is rendered open, so that the band 1 is stored in a pool box 4. The pool box 4 is formed into a small thickness so as to correspond to a thickness of the band 1, so that the band 1 is stored in the pool box 4 while being folded in due turn, resulting in entangling of the band in the pool box being effectively prevented.
The band guide plate means 8, as shown in FIG. 14, is constructed so as to be pivotally moved about a shaft 8a mounted on a side wall 3 of the pool box 4. The band guide plate means 8 includes a distal end 8b, which is positioned in proximity to a side wall of the pool box 4 opposite to the side wall 3 of the pool box 4 when the band guide plate means 8 is kept closed. This causes the band guide plate means 8 to form a band guide passage 6 between the guide plate means 8 and a rear wall 9 of the pool box 4 at an upper end of the pool box 4, resulting in the band 1 being guided in the passage 6. When the band guide plate means 8 is rendered open to release the band guide passage 6, the band 1 is stored in the pool box 4 as indicated at two-dot chain lines in FIGS. 13 and 14.
Unfortunately, the conventional band charging apparatus requires that when the band 1 is guided along the band guide pate means 8, to thereby be charged in the band feeding and charging apparatus, an operator manually opens the band guide plate means 8 after confirming completion of the charging. The confirmation is highly troublesome. Also, in the conventional band charging apparatus, it is highly difficult to open the band guide plate means 8 in time with the confirmation. If opening of the band guide plate means 8 is delayed, there occurs a possibility of causing jamming of the band at a position where the band is forwardly moved from the band feeding and tightening apparatus. The jamming prevents smooth drawing-back of the band.